[comp.sys.att] AT&T EGA 750 display adapter info wanted

lyourk@ihlpf.ATT.COM (Loran N. Yourk) (07/30/88)

I have an AT&T 6300 Plus computer with an AT&T 318H color monitor
and would like any information on the AT&T 750 EGA card in such a
system.  I would like to know what modes are supported (CGA, HERC,
EGA, AT&T, DEB, etc.,) and how well it works with software such as
GEM and others.  How is the speed of the card and does it use the
"AT&T 16 bit bus" or is it just an 8 bit card?  Does anyone know
of any problems of using it in an AT&T 6300 Plus with UNIX(TM)
software (I do not have the UNIX(TM) software yet but...)?

I know TAXAN makes the 557 Gold EGA video card but how does it
compare to the AT&T 750 card.  Which would be better or are they
the same?

[I already have the video disabler chip and installation
instructions for EGA cards in the 6300 Plus.]

Loran Yourk
ihlpf!lyourk
(312) 510-6885

psc@lznv.ATT.COM (Paul S. R. Chisholm) (08/01/88)

< "Would you buy a used operating system from these guys?" >

In article <5481@ihlpf.ATT.COM>, lyourk@ihlpf.ATT.COM (Loran N. Yourk) writes:
> I have an AT&T 6300 Plus computer with an AT&T 318H color monitor
> and would like any information on the AT&T 750 EGA card in such a
> system.

So far as I understand, it's a fairly vanilla EGA card, except that it
does CGA (and AT&T 640x400) at 25MHz.  It runs the 319 color monitor at
the regular (not 25 MHz) EGA frequency, so you *can't* use the 318.
(That's right, the 319 is not a multifrequency but a *bi*frequency
monitor!)

>                  How is the speed of the card and does it use the
> "AT&T 16 bit bus" or is it just an 8 bit card?

If it works in a 6310 or WGS system (and it does), it can't use the
AT&T sixteen bit bus.

>                                                 Does anyone know
> of any problems of using it in an AT&T 6300 Plus with UNIX(TM)
> software (I do not have the UNIX(TM) software yet but...)?

This specific card, I don't know.  There's not a lot of UNIX(R)
software that understands EGAs.  (Especially not UNIX software written
for the 6300 PLUS, which can't take an EGA without minor surgery.)

> I know TAXAN makes the 557 Gold EGA video card but how does it
> compare to the AT&T 750 card.  Which would be better or are they
> the same?

The STB Multires II will put EGA graphics (sixteen simultaneous colors
out of a palette of sixteen instead of sixty-four) on your 318 monitor.
The Taxan 557 Gold Card *should* do the same thing, but when I asked
about a year ago, Taxan wouldn't confirm this.

Note for old 6300 (not PLUS) owners:  EGA cards are incompatible with
the 384K memory expansion boards.  So sorry.

> [I already have the video disabler chip and installation
> instructions for EGA cards in the 6300 Plus.]

Good, you'll need them.

> Loran Yourk, ihlpf!lyourk, (312) 510-6885

-Paul S. R. Chisholm, {ihnp4,cbosgd,allegra,rutgers}!mtune!lznv!psc
AT&T Mail !psrchisholm, Internet psc@lznv.att.com
I'm not speaking for my employer, I'm just speaking my mind.
UNIX(R) is a registered trademark of AT&T.

rps@homxc.UUCP (R.SHARPLES) (08/01/88)

In article <1428@lznv.ATT.COM>, psc@lznv.ATT.COM (Paul S. R. Chisholm) writes:
> In article <5481@ihlpf.ATT.COM>, lyourk@ihlpf.ATT.COM (Loran N. Yourk) writes:
> > I have an AT&T 6300 Plus computer with an AT&T 318H color monitor
> > and would like any information on the AT&T 750 EGA card in such a
> > system.
> 
> So far as I understand, it's a fairly vanilla EGA card, except that it
> does CGA (and AT&T 640x400) at 25MHz.  It runs the 319 color monitor at
> the regular (not 25 MHz) EGA frequency, so you *can't* use the 318.
> (That's right, the 319 is not a multifrequency but a *bi*frequency
> monitor!)
> 
> > I know TAXAN makes the 557 Gold EGA video card but how does it
> > compare to the AT&T 750 card.  Which would be better or are they
> > the same?
> 
> The STB Multires II will put EGA graphics (sixteen simultaneous colors
> out of a palette of sixteen instead of sixty-four) on your 318 monitor.
> The Taxan 557 Gold Card *should* do the same thing, but when I asked
> about a year ago, Taxan wouldn't confirm this.
> 

I have installed and used both the TAXAN 557 and the STB EGA Multires II.
I highly recommend the STB.  The Taxan supports Taxan's proprietary video
mode which is 640x400x16 (though not compatible with the AT&T DEB).  EGA
is supported *only* through software emulation.  Hence, any software that
tries to write directly to the EGA hardware registers (virtually anything
by Microsoft) will encounter problems on the Taxan card.  The STB card
on the other hand is fully register compatible with the EGA, supports
a 640x400 text mode (so you get clearer text than EGA's 640x350 text mode)
and will run 640x350x16 EGA graphics on an AT&T 318.  The EGA image is smaller
than full screen because 50 lines are blank due to the difference in 
horizontal resolutions.

Russ Sharples
homxc!rps

NOTE:

The above in NO WAY reflects the opinions of AT&T.
These opinions are my own and the results of un-scientific and 
highly irregular analysis methods.

aptr@ur-tut (The Wumpus) (08/02/88)

In article <1428@lznv.ATT.COM> psc@lznv.ATT.COM (Paul S. R. Chisholm) writes:
>< "Would you buy a used operating system from these guys?" >
>
>In article <5481@ihlpf.ATT.COM>, lyourk@ihlpf.ATT.COM (Loran N. Yourk) writes:
>> I have an AT&T 6300 Plus computer with an AT&T 318H color monitor
>> and would like any information on the AT&T 750 EGA card in such a
>> system.
>
>So far as I understand, it's a fairly vanilla EGA card, except that it
>does CGA (and AT&T 640x400) at 25MHz.  It runs the 319 color monitor at
>the regular (not 25 MHz) EGA frequency, so you *can't* use the 318.
                                                ^^^^^^^
Don't tell me this.  My monitor will be really upset when it finds out
that it should not have been running on the VDC750.  I have had a VDC
750 installed in my 6300 clone for a month with no problems from the
monitor.

In the VDC 750 Manual, it states that the card _will_ work the 318 monitor,
but there are some small problems.   The first of these is that the
screen is slightly compressed due to the difference in scan lines between
the EGA and AT&T modes (350 vs. 400).  The second is that the 318 will
not display all 64 possible colors, only the 16 colors that could
be displayed in normal CGA.

I should also point out that the VDC 750 adds an Extended EGA mode
that is 640x400 16 color.  It is not the same as DEB, but it is
still very nice.

PS: The VDC 750 comes with instructions for installing it in almost
all of the 63xx machines except the 6300.  When I called AT&T about
this when I got the card (a month or so ag), they were not officially
supporting any EGA card in the 6300 because of the Bus problem.  Since
then, I have found a correction for the Bus problem and apparently,
the VDC 750 is becoming popular in 6300s inside of AT&T.

-- 
The Wumpus        UUCP:   {cmcl2!decvax}!rochester!ur-tut!aptr
                  BITNET: aptrccss@uorvm
		  Internet: aptr@tut.cc.rochester.edu
Disclaimer: "Who? When? Me? It was the Booze!"  - M. Binkley
-- 
The Wumpus        UUCP:   {cmcl2!decvax}!rochester!ur-tut!aptr
                  BITNET: aptrccss@uorvm
		  Internet: aptr@tut.cc.rochester.edu
Disclaimer: "Who? When? Me? It was the Booze!"  - M. Binkley

mcripps@mtuxo.att.com (XMP12-M.CRIPPS) (08/05/88)

In article <1428@lznv.ATT.COM>, psc@lznv.ATT.COM (Paul S. R. Chisholm) writes:
> So far as I understand, it's a fairly vanilla EGA card, except that it
> does CGA (and AT&T 640x400) at 25MHz.  It runs the 319 color monitor at
> the regular (not 25 MHz) EGA frequency, so you *can't* use the 318.
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^

The above paragraph isn't quite right.  First off, the VDC750 works with
the 318 just fine.  The VDC750 has a dip switch to select the scan rate.
It will work with IBM compatible monitors and AT&T monitors (25Khz, not Mhz).
Furthermore, the 319 does NOT run at the "regular" EGA frequency.  The
manual says clearly that the scan rate switch should NEVER be set to IBM
when you are using an AT&T monitor.  Lastly, the VDC750, while fairly
vanilla by industry standards, does do a 640x400 16-color enhanced EGA
mode (if you can find software to support it).  Note that this mode is not
DEB compatible.

Mike Cripps
AT&T Bell Labs
Lincroft, NJ
mtuxo!mcripps

aptr@ur-tut (The Wumpus) (08/06/88)

In article <2307@mtuxo.att.com> mcripps@mtuxo.att.com (XMP12-M.CRIPPS) writes:
>... Lastly, the VDC750, while fairly
>vanilla by industry standards, does do a 640x400 16-color enhanced EGA
>mode (if you can find software to support it).  Note that this mode is not
>DEB compatible.

Actually getting software to support the 640x400 mode is not really
that difficult it you don't mind a doing patches. (Me, I don't mind,
but I also like FORTH.)  Anyways, I have already patched several
programs to makje use of the 640x400 16 color display.  Usually, the
only real changes that need to be made are to locations that store
screen size and the mode number.  If the program supports the Paradise
AutoSwitch EGA Extended EGA mode (640x480 16 color), the patch is very
simple.  The VDC750 is just a modified Paradise that has AT&T 640x400
Mono instead of Hercules and 640x400 EGA instead od 640x480.

Some of the programs I have thus far patched to run 640x400 16 color
mode are:
	Publisher's Paintbrush 
	Orcad Schematic Capture (circuit design) 
	Prodesign 2.0	(CAD)
I am pretty sure I got some others to work, but I can't think what
they were right now.

If there is any interest I am willing to tell people how to make the
patches to the programs I have patched (I beleive copyright laws may
prohibit the distribution of the drivers, and possibly the patching of
them.)  I am also willing to describe what to look for and how to
change it in other programs.

---
John Werner
    aka
The Wumpus        UUCP:   {cmcl2!decvax}!rochester!ur-tut!aptr
                  BITNET: aptrccss@uorvm
		  Internet: aptr@tut.cc.rochester.edu
Disclaimer: "Who? When? Me? It was the Booze!"  - M. Binkley
-- 
The Wumpus        UUCP:   {cmcl2!decvax}!rochester!ur-tut!aptr
                  BITNET: aptrccss@uorvm
		  Internet: aptr@tut.cc.rochester.edu
Disclaimer: "Who? When? Me? It was the Booze!"  - M. Binkley